Bypassed alignment graph for learning coordination in Japanese sentences

Past work on English coordination has focused on coordination scope disambiguation. In Japanese, detecting whether coordination exists in a sentence is also a problem, and the state-of-the-art alignmentbased method specialized for scope disambiguation does not perform well on Japanese sentences. To take the detection of coordination into account, this paper introduces a ‘bypass’ to the alignment graph used by this method, so as to explicitly represent the non-existence of coordinate structures in a sentence. We also present an effective feature decomposition scheme based on the distance between words in conjuncts.